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A239446 Triangle read by rows: T(n,k), n>=1, k>=1, in which column k lists the elements of A004273 interleaved with k zeros, and the first element of column k is in row k*(k+1)/2.

%I A239446 #12 Mar 13 2015 18:09:45
%S A239446 0,0,1,0,0,0,3,0,0,1,0,5,0,0,0,0,0,7,3,0,0,0,1,0,9,0,0,0,0,5,0,0,11,0,
%T A239446 0,0,0,0,3,0,13,7,0,1,0,0,0,0,0,0,15,0,0,0,0,0,9,5,0,0,17,0,0,0,0,0,0,
%U A239446 0,3,0,19,11,0,0,1,0,0,0,7,0,0,0,21,0
%N A239446 Triangle read by rows: T(n,k), n>=1, k>=1, in which column k lists the elements of A004273 interleaved with k zeros, and the first element of column k is in row k*(k+1)/2.
%C A239446 Alternating sum of row n equals A235796(n), i.e., sum_{k=1..A003056(n)} (-1)^(k-1)*T(n,k) = A235796(n).
%C A239446 Row n has length A003056(n) hence column k starts in row A000217(k).
%C A239446 Column k starts with k+1 zeros and then lists the odd numbers interleaved with k zeros.
%C A239446 It appears that row n lists all zeros iff n is a power of 2.
%e A239446 Triangle begins:
%e A239446 0;
%e A239446 0;
%e A239446 1,  0;
%e A239446 0,  0;
%e A239446 3,  0;
%e A239446 0,  1,  0;
%e A239446 5,  0,  0;
%e A239446 0,  0,  0;
%e A239446 7,  3,  0;
%e A239446 0,  0,  1,  0;
%e A239446 9,  0,  0,  0;
%e A239446 0,  5,  0,  0;
%e A239446 11, 0,  0,  0;
%e A239446 0,  0,  3,  0;
%e A239446 13, 7,  0,  1,  0;
%e A239446 0,  0,  0,  0,  0;
%e A239446 15, 0,  0,  0,  0;
%e A239446 0,  9,  5,  0,  0;
%e A239446 17, 0,  0,  0,  0;
%e A239446 0,  0,  0,  3,  0;
%e A239446 19, 11, 0,  0,  1,  0;
%e A239446 0,  0,  7,  0,  0,  0;
%e A239446 21, 0,  0,  0,  0,  0;
%e A239446 0,  13, 0,  0,  0,  0;
%e A239446 23, 0,  0,  5,  0,  0;
%e A239446 ...
%e A239446 For n = 15 the 15th row of triangle is 13, 7, 0, 1, and the alternating sum is 13 - 7 + 0 - 1 = A235796(15) = 5.
%Y A239446 Cf. A000203, A000217, A003056, A004125, A004273, A196020, A231345, A231347, A235791, A235794, A235796, A236106, A236104, A236112, A237048, A237588, A237591, A239313.
%K A239446 nonn,tabf
%O A239446 1,7
%A A239446 _Omar E. Pol_, Mar 20 2014